A few days ago, Southampton teenager Adam Hunt’s friends met up to play football. He wasn’t there. The bright 18-year-old had been laid to rest at a church the previous day. Adam, who had passed 11 GCSEs and was studying electrical engineering at college, died after taking the legal high AMT last month.

The proceeds of that fundraising game, which was arranged in memory of the keen Southampton FC supporter, will go to the intensive care unit at Southampton General Hospital, where he spent five days before he passed away.

In the past year, police in Hampshire have had to deal with three “extremely serious” cases involving AMT, a psychedelic drug that releases serotonin and can have effects similar to LSD and ecstasy. It won’t be long before another youngster ends up in hospital.

A stark report published this week by Iain Duncan Smith’s Centre for Social Justice (CSJ) has warned that Britain is now the “addicted man of Europe” with some of the highest rates of substance abuse.

The report highlights particular concern over legal highs, ordered online and delivered by postal workers operating as unwitting “drug mules”. At least one in 12 young people in the UK – more than 670,000 - have already tried legal highs, which have been linked to an 80 per cent rise in deaths in the past year (from 29 to 52). Britain is now regarded as a global hub for websites selling the drugs.

Every few days a new variety of legal high goes on sale, specifically packaged to appeal to youngsters. Teenage party invitations come with web links advertising where to buy the drugs. More than 70 new varieties were recorded in 2012. The number is expected to exceed that this year. While the use of traditional drugs is in gradual decline, those on the frontline say they are losing the fight to control the new wave of drugs, which come in the form of pills, powders and even canisters of laughing gas, swamping Britain.

“This report should be a huge wake-up call for the Government,” says Andrew Griffiths, the Conservative MP for Burton and Uttoxeter who was part of the CSJ working group that compiled the study. “Gone are the days where drug taking and addiction were the scourge of the working classes – it now stretches from the council estate to leafy shires. You no longer have to know a dealer and meet them on the street. You can have a postman bring it to your front door.”

In England, 6,486 people were treated in 2011-12 for abusing legal highs, an increase of 39 per cent compared with five years previously. So many new legal highs are now available, it is impossible for researchers to keep up. They range from GBL – an industrial solvent used to clean metals that is technically banned, but easy to buy and has been linked to numerous deaths, – to nitrous oxide, better known as laughing gas.

Data compiled by the Home Office on laughing gas showed that it was inhaled by at least 350,000 16-24-year-olds last year.

It is now the second-most popular drug among young people after cannabis and is freely available to buy – including on some of the best-known shopping websites. Doctors warn it can lead to strokes, seizures, even death. Last August, Joe Benett, a 17-year-old public schoolboy, suffered a heart attack and brain damage after taking what he thought was laughing gas at a party with friends. It turned out to be a cocktail of toxic gases, including butane and pentane, used to make polystyrene.

Earlier this year, Home Office Minister Jeremy Browne wrote to festival organisers highlighting concerns about the availability of nitrous oxide. None the less, the telltale whoosh of balloons being filled with the gas has been present at festivals throughout the summer from Reading to Wilderness, known as “Poshstock”, where Bank of England Governor Mark Carney stepped carefully among giggling users in his suede loafers.

“We are never going to win by controlling the supply, so what we have got to do is try to educate children that taking untested chemicals is very dangerous,” says toxicologist Dr John Ramsey, whose organisation TicTac helps produce a drug database used by law enforcement and health professionals. Dr Ramsey’s concern, like that of many others, is that the long-term health implications of these legally bought drugs are entirely unknown.

Police and health workers point to what is currently being seen with users of ketamine, a horse tranquiliser which was previously legal but classified as a Class C drug in 2006, as a sign of the long-term risks of legal highs.

The drug has been at the vanguard of the surge in use of so-called party drugs. But in the past year urologists in Britain have started to report a significant rise in cases of ketamine users having to wear nappies, or having their bladders removed altogether due to the drug.

“Young people will be going out this weekend and taking these new legal highs and they haven’t got a clue about the long-term effects,” says Bryan Dent, drugs coordinator for West Yorkshire Police. “It’s just like the people who started using ketamine a few years ago. They wouldn’t have seen themselves in 2013 having to go to the toilet 150 times a day.”

Kate, who now works in a London gallery, first took ketamine in 2004 during her GCSE year, getting it from older friends who bought it over the internet from India. Her use of the drug rose, she ended up weighing six stone and in constant agony. She even set fire to the squalid East London flat she shared with five dealers in order to steal their supply.

Only now, aged 25, and clean after being told that her bladder needed to be removed (an operation she refused to have done), does the bright graduate fully appreciate the horrors of her addiction.

“During A-levels we were taking drugs at school. A lot of girls joined the sixth form from a posh private school nearby. We would wait until the teacher had turned their back and snort lines of ketamine off our desks. I lived with my mum and she was terrified. I was out of control.”

Kate went on to university, where her use of ketamine escalated. By the time she graduated, she says, “I had to take it every hour to get through the day. It still felt cool. The reality was I was in agony, peeing into a bottle because I couldn’t make it into the toilet.”

Worryingly, access to these drugs has become even easier since Kate’s drug-taking days. Crystal, a 24-year-old from London who only came out of rehab earlier this year after developing an addiction to the now banned legal high, mephedrone, says it is “frighteningly easy” to start selling the drugs online.

“When we were still teenagers my boyfriend started a business,” she said. “They found themselves a supplier in China, got it shipped over and then set up a website. They were selling kilos of the drug to people as far away as South Africa. It made us all feel pretty big.”

The business was raided by police soon after mephedrone, known as miaow miaow, became a Class B drug in 2010. Crystal, however, was long-addicted by that point. “Legal highs fry your brain. Nobody knows what goes in them. That’s why they’re so dangerous.”

As well as websites, growing numbers of so-called head shops are springing up across the country. They openly advertise legal highs, which can be sold as long they are marked “not fit for human consumption” and only bought by people aged over 18. There is also concern that traditional drug gangs are moving into the trade.

Police remain hamstrung by antiquated legislation – the Misuse of Drugs Act was devised in 1971. Earlier this year, West Yorkshire Police carried out the first raid on a head shop selling legal highs to minors. Officers dusted off the obscure Intoxicating Substances Act of 1985, originally introduced to combat glue sniffing. The shop owner was found guilty and given a 12-month conditional discharge.

Since 2010, the Government has imposed three temporary banning orders to control approximately 15 substances. Each time, a chemical formula is tweaked, and factories in India and China, which mass-produce legal highs for the global market, churn out countless other similar drugs ready for sale.

Britain’s addiction to drugs and alcohol is now costing the taxpayer £36 billion a year. Despite the dangers, our appetite for destruction seems voracious. Perhaps it has always been so. Aldous Huxley and George Orwell could not envisage a futuristic Britain without drugs, be it 1g of Soma or a bottle of gin.

Yet nothing has quite prepared us for the rise of the legal high generation. We can’t stop them getting the drugs. And more worrying, we still don’t know what, in the long run, the dangers of this Brave New World will be.